Blast-furnace



2 Sheets-Sheet 1. I

J. M. .HARTMAN.

Blast Furnace.

No. 229,883. Patented July 13, 1880.

rLPErERs PHOTO UTMDGRAPHZR. WASHINGTON D O 2 Sheets-Sheet 2.

J. M HARTMAN. Blast Furnace. No. 229,883. Patented Juiy 13, 1880.

' %Zneddad.

@iuu llgfwmma, QM

N.PETERS, PMOTO LITHOGRAVHER, WASNXNGTON. D O.

UNITED STATES PATENT Orin-ca.

JOHN M. HARTMAN, OF PHILADELPHIA, PENNSYLVANIA.

BLA'ST-FU RNAC E.

SPECIFICATION forming part of Letters Patent No. 229,883, dated July 13, 1880.

Application filed December 10, 1878.

To all whom it may concern:

Be it known that I, J OHN M. HARTMAN, of Philadelphia, in the countyof Philadelphia and State of Pennsylvania, have invented a new and useful Improvement in Blast-Furnaces, which improvement is fully set forth in the following specification and accompanying drawings, in which Figure 1 is a general plan of the works. Fig. 2 shows the interior of the pivot-valve. Fig. 3 shows the construction of the air-surging valve. Fig. 4 shows mode of connecting the hustle and tuyere pipes. Fig. 5 shows the automatic operation of the equalizing-valve.

The nature of my invention consists in an improved combination of appliances to prevent the accumulation of dust upon the walls of the fire-brick regenerator also, in combining with the regenerator avalve which maybe suddenly opened to discharge dust with a surging pressure of the air; also, in an apparatus by which the heat is retained in the stove at the commencement of the blow, and utilized at the end of the blow, by an automatic valve; also, in the construction of the pipe where the hot and cold blast commingle; also, in the construction of the bustle-pipe in straight segments lined with fire-brick, which are bolted together by bevel-flanges also, in connecting the bustle-pipe to the belly-pipe of the tuyere by means of a fixed depending branch lined through the stove its heat is lowered, so that a pyrometer can be used in its escaping gas with fire-brick. I

I11 operating regenerative fire-brick stoves,

one of which is shown at A, the gases from the 5 blast-furnace deposit dust on the walls of the stove, which destroys their efficiency and requires the walls to be frequently cleaned. When the stoves are heated to a high temper ature this dust fuses on the walls and destroys them.

A gas-washing apparatus does not remove all the dust. The bulk of the powder passing the washer collects on the cold side of the stove near valve 0.

The stoves are changed every four hours, and after a stove is cut oif from the furnace it is left full of compressed air, which must be got rid of. At the extreme bottom of the stove, on the cold side, I place a surging dust-valve, O, which, by means of a bolt or trip, is caused to fly open suddenly. The air in the stove expands, rushes out through this valve, and carries ofi' part of the fine powder. This valve relieves the pressure, carries off part of the powder, and, to the extent the powder is carried off, the stoves are rendered more efficient.

The construction of the air-surging valve is shown in Fig. 3.

.The valve consists of a hinged door, closed by a lever-bolt, 0 By withdrawing this lever or bolt the valve opens instantly. To remove this powder I blow through the stoves about every two days a large volume of blast from the furnace-blowing engine, which sweeps it out of the stove. is provided with a pivot-valve, B, (shown in Fig. 2,) or any similar valve which can be suddenly opened, by which the air can be surged through the stove intermittingly. On the opposite side of the stove from the said pivot-valve there is a surging dust-door, 0, similar to 0, which is thrown 'open when surging the air through the stove for the escape of the air and dust. By means of the conjoined operation of a gas-washin g apparatus, the air-surgingpivotvalve B, and the dust-surging valve G, I keep the stoves clean.

To regulate the amoun'tof gas in a stove has been heretofore difiicult, as no pyrometer has without being destroyed.

Byinserting a pyrometer, G, in this escaping 'gas a proportion can soon be established that will enable the-operator to govern the stove completely. For instance, I find that with escaping gas going off at 400 the blast when turned on will give 1,100 on the hot side of the stove, and if I wish to run 1,200 then the escaping gas must be raised in temperature to correspond by adding more gas.

The time astove is on the furnace is-usually two hours. It is called a blow,and is thetime the air is being blown through one of the stoves. When a fire-brick stove is heated up and the blast turned through it on the furnace the temperature will be, perhaps, 1,300 Intwohours this will lower to 1,100 This variation deranges the working of the furnace and changes For this purpose the stove cold air mixing with the hot-blast reduces its temperature when working, as in the above-described case, to about 1,200 Now the cold air that has passed direct has not robbed the stove of the heat that it would have received had it passed through the stove; consequently that heat is retained inthe stove.

To the valve E above mentioned is attached any well known movement, such as clockwork or a float and cataract. This latter is made in this way: A steam cylinder placed upright has a piston sliding loosely within it. The piston-rod is attached to the stem of the equalizing-valve E. (See Fig. 1.) In the piston is a check-vah'e opening downward, and also a simple hole drilled through the piston. The cylinder is filled with glycerine. It operates this way: The piston is raised by hand, opening the valve E. As the piston descen ds by gravity the glycerine passes through the hole to the top side, the hole being of such a size as to allow it to escape in two hours. Either of these plans described herein will gradually close the valve toward the latter part of the blow, by which more air will pass by the stove at the commencement of the blow, and less pass direct to the hot-blast pipe N. By this means the heat held in reserve at the beginning of the blow will be given up toward the latter part of the blow and a more uniform temperature maintained.

When the difierence in pressure between the hot and cold side of the stove is considerable, which pressure is due to friction through the stove, I use a puppet-valve which can be adjusted by weights, which will cause it to gradually close by thechange of pressure.

To make the cold air enter the hot-blast and mix thoroughly with it, I continue the coldblast-pipe nozzle H through the hot-blast pipe into the connection to the circular pipe. The hot-blast passing along outside of this pipe forms a suction which draws the cold air with it and mixes it thoroughly.

The fire-brick stoves are placed up close to the furnace and discharge immediately into the pipe running around the furnace. This pipe is usually called a bustle-pipe. Itforms a circle around the furnace and is lined with fire-brick of one or more thicknesses. This pipe is costly to make and extremely diflicult to line with the brick. To obviate this I form it of straight segments K, with angle-flanges. These straight pipes I line with fire-brick,

and after being lined I bolt them together in position.

Heretofore the tuyere-pipe leading from the bustle-pipe to the furnace has been attached to the bustle-pipe direct. This long exposed tuyere-pipe is heax'y to handle and causes great loss of heat by radiation. 1 make one or more of the branches K of the bustle-pipe with a branch, as shown in Fig. 4, which is also lined with fire-brick. The tuyere-pipe k can then be made quite short, can'be easily handled,and causes only a small loss by radiation. This is an important feature in the connections of. the hot-blast stoves where the temperature of blast is over red heat.

One of the automatic arrangements for closing the equalizing-valve E is shown in Fig. 5. It consists of a clock-work mechanism operating the pendulum c and escapement c and by means of a screw upon the spindle e of the valve it is gradually closed.

What I claim as my invention is- 1. In combination with a regenerative firebrick stove, the cold-blast main M, a pivotvalve, the hot-blast main N, and dust-discharge outlets, whereby a sudden discharge of blast is produced, as herein described.

2. The combination, with a regenerative tirebrick stove, of the cold-air main M and the valve 0, with hinged door 0 and bolt 0 whereby is produced a sudden pufl' of blast and discharge of dust, as herein described.

3. The combination of the cold-blast main M, the connecting-pipe R, equalizing-valve E, and the nozzle H, projecting in within the hotblast pipe, as described.

4. The bustle-pipe of a blast furnace, constructed in segments K, having beveled flanges and lined with firebrick, as herein described.

5. In combination with the bustle-pipe of a blast-furnace, a depending branch, k lined with fire-brick, for connecting to the tuyerepipe, as herein described.

6. In combination with a fire-brick regenerative stove, a cold-air main leading into the stove, and ahot-air main, N, leading from the stove to the furnace, a cold-air pipe, R, connecting the cold-air main M with the hot-air pipe N, I

and a regulating-valve, E, in the pipe R, in combination with automatic mechanism for gradu- IIO ally closing said valve toward the end of the JOHN M. H-ARTMAN.

Witnesses:

EDWD. BROWN, JOHN F. GRANT. 

